nghttp2_hd: Provide dedicated function to enable no reference set feature

hdtest/deflatehd.c

@@ -384,8 +384,8 @@ int main(int argc, char **argv)
       break;
     }
   }
-  nghttp2_hd_deflate_init2(&deflater, config.side, config.deflate_table_size,
-                           config.no_refset);
+  nghttp2_hd_deflate_init2(&deflater, config.side, config.deflate_table_size);
+  nghttp2_hd_deflate_set_no_refset(&deflater, config.no_refset);
   nghttp2_hd_change_table_size(&deflater, config.table_size);
   if(config.http1text) {
     perform_from_http1text(&deflater);

lib/nghttp2_hd.c

@@ -246,14 +246,13 @@ static void nghttp2_hd_ringbuf_pop_back(nghttp2_hd_ringbuf *ringbuf)
 static int nghttp2_hd_context_init(nghttp2_hd_context *context,
                                    nghttp2_hd_role role,
                                    nghttp2_hd_side side,
-                                   size_t deflate_hd_table_bufsize_max,
-                                   uint8_t no_refset)
+                                   size_t deflate_hd_table_bufsize_max)
 {
   int rv;
   context->role = role;
   context->side = side;
   context->bad = 0;
-  context->no_refset = no_refset;
+  context->no_refset = 0;
   context->hd_table_bufsize_max = NGHTTP2_HD_DEFAULT_MAX_BUFFER_SIZE;
   rv = nghttp2_hd_ringbuf_init
     (&context->hd_table,
@@ -279,24 +278,20 @@ static int nghttp2_hd_context_init(nghttp2_hd_context *context,
 int nghttp2_hd_deflate_init(nghttp2_hd_context *deflater, nghttp2_hd_side side)
 {
   return nghttp2_hd_context_init(deflater, NGHTTP2_HD_ROLE_DEFLATE, side,
-                                 NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE,
-                                 0);
+                                 NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE);
 }
 
 int nghttp2_hd_deflate_init2(nghttp2_hd_context *deflater,
                              nghttp2_hd_side side,
-                             size_t deflate_hd_table_bufsize_max,
-                             uint8_t no_refset)
+                             size_t deflate_hd_table_bufsize_max)
 {
   return nghttp2_hd_context_init(deflater, NGHTTP2_HD_ROLE_DEFLATE, side,
-                                 deflate_hd_table_bufsize_max,
-                                 no_refset);
+                                 deflate_hd_table_bufsize_max);
 }
 
 int nghttp2_hd_inflate_init(nghttp2_hd_context *inflater, nghttp2_hd_side side)
 {
-  return nghttp2_hd_context_init(inflater, NGHTTP2_HD_ROLE_INFLATE, side, 0,
-                                 0);
+  return nghttp2_hd_context_init(inflater, NGHTTP2_HD_ROLE_INFLATE, side, 0);
 }
 
 static void nghttp2_hd_context_free(nghttp2_hd_context *context)
@@ -329,6 +324,12 @@ void nghttp2_hd_inflate_free(nghttp2_hd_context *inflater)
   nghttp2_hd_context_free(inflater);
 }
 
+void nghttp2_hd_deflate_set_no_refset(nghttp2_hd_context *deflater,
+                                      uint8_t no_refset)
+{
+  deflater->no_refset = no_refset;
+}
+
 static size_t entry_room(size_t namelen, size_t valuelen)
 {
   return NGHTTP2_HD_ENTRY_OVERHEAD + namelen + valuelen;

lib/nghttp2_hd.h

@@ -188,9 +188,6 @@ int nghttp2_hd_deflate_init(nghttp2_hd_context *deflater,
  * for header table even if the larger value is specified later in
  * nghttp2_hd_change_table_size().
  *
- * If nonzero is given in the |no_refset|, the encoder first clears
- * the reference set each time on deflation.
- *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes:
  *
@@ -199,8 +196,7 @@ int nghttp2_hd_deflate_init(nghttp2_hd_context *deflater,
  */
 int nghttp2_hd_deflate_init2(nghttp2_hd_context *deflater,
                              nghttp2_hd_side side,
-                             size_t deflate_hd_table_bufsize_max,
-                             uint8_t no_refset);
+                             size_t deflate_hd_table_bufsize_max);
 
 /*
  * Initializes |inflater| for inflating name/values pairs.
@@ -224,6 +220,14 @@ void nghttp2_hd_deflate_free(nghttp2_hd_context *deflater);
  */
 void nghttp2_hd_inflate_free(nghttp2_hd_context *inflater);
 
+/*
+ * Sets the availability of reference set in the |deflater|. If
+ * |no_refset| is nonzero, the deflater will first emit index=0 in the
+ * each invocation of nghttp2_hd_deflate_hd() to clear up reference
+ * set. By default, the deflater uses reference set.
+ */
+void nghttp2_hd_deflate_set_no_refset(nghttp2_hd_context *deflater,
+                                      uint8_t no_refset);
 
 /*
  * Changes header table size in |context|. This may trigger eviction

tests/nghttp2_hd_test.c

@@ -278,7 +278,7 @@ void test_nghttp2_hd_deflate_deflate_buffer(void)
   /* Check the case where entry from static table is inserted to
      dynamic header table. And it is out of deflate header table
      size. */
-  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 32, 0);
+  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 32);
   nghttp2_hd_inflate_init(&inflater, NGHTTP2_HD_SIDE_REQUEST);
   blocklen = nghttp2_hd_deflate_hd(&deflater, &buf, &buflen, 0,
                                    nva4, ARRLEN(nva4));
@@ -310,7 +310,7 @@ void test_nghttp2_hd_deflate_deflate_buffer(void)
   nghttp2_hd_inflate_free(&inflater);
 
   /* 156 buffer size can hold all headers in deflate region */
-  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 156, 0);
+  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 156);
   blocklen = nghttp2_hd_deflate_hd(&deflater, &buf, &buflen, 0,
                                    nva1, ARRLEN(nva1));
   CU_ASSERT(blocklen > 0);
@@ -344,7 +344,7 @@ void test_nghttp2_hd_deflate_deflate_buffer(void)
   nghttp2_hd_deflate_free(&deflater);
 
   /* Check more complex use case */
-  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 155, 0);
+  nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST, 155);
   nghttp2_hd_inflate_init(&inflater, NGHTTP2_HD_SIDE_REQUEST);
   blocklen = nghttp2_hd_deflate_hd(&deflater, &buf, &buflen, 0,
                                    nva1, ARRLEN(nva1));
@@ -452,7 +452,8 @@ void test_nghttp2_hd_deflate_clear_refset(void)
   size_t i;
 
   nghttp2_hd_deflate_init2(&deflater, NGHTTP2_HD_SIDE_REQUEST,
-                           NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE, 1);
+                           NGHTTP2_HD_DEFAULT_MAX_DEFLATE_BUFFER_SIZE);
+  nghttp2_hd_deflate_set_no_refset(&deflater, 1);
   nghttp2_hd_inflate_init(&inflater, NGHTTP2_HD_SIDE_REQUEST);
 
   for(i = 0; i < 2; ++i) {